No luck with wi-fi on x86_64

Hi all
I am interested in migrating from Linux to NetBSD as I find the NetBSD
approach to what an OS should be like neater. There is however a major
snag in that none of the wi-fi adapters I have seem to agree with
NetBSD-5.{0.2;1}-amd64 on my Vaio laptop (Vaio VGN-SZ7RVN)
The built-in Intel 3945 (wpi), seems to have firmware problems on
amd64 (prints out the error message: "fatal firmware error" whenever I
try to bring it up - there is no such problem on i386 port and it
works with other OSs so the hardware is fine). I have tried various
firmware versions with no success. There seems to be a PR with exactly
the same problem described but it appears it hasn't been followed up
since it was posted (http://gnats.netbsd.org/41833).
Having heard that Atheros-based cards are better supported I got one
of them - a TP-Link TL-WN310G CardBus adapter. Alas this also didn't
work causing a kernel panic whenever the adapter is inserted. Again I
have checked the hardware with my linux and NetBSD/i386 installation
and it is working. Again there is a PR (http://gnats.netbsd.org/41175)
with not much in the way of follow-up.
The reason why I don't want to go with the 32 bit port is that I have
4GB of ram and it seems silly to not use a gig having paid for it in
the first place. Could you please enlighten me if there are any ways
of getting around these wi-fi problems or indeed wi-fi adapters that
definitely will work with the amd64 port.
Many thanks
Ilya